Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from beak.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests) ID ; Fri, 12 Jan 90 01:34:22 -0500 (EST) Message-ID: Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Fri, 12 Jan 90 01:33:58 -0500 (EST) Subject: SPACE Digest V10 #417 SPACE Digest Volume 10 : Issue 417 Today's Topics: Communications satellites Why did Solar Max fall but space junk stays up? ---------------------------------------------------------------------- Date: 11 Jan 90 22:38:15 GMT From: meccts!meccsd!jap@UMN-CS.CS.UMN.EDU (John A. Persoon) Subject: Communications satellites I have a few questions I hope someone out there in net.land can answer for me. How many communications satellites are currently in orbit around the earth? How many are operational? How many of those are for military vs. public/commercial? How many of those are for strictly commercial use in the U.S.? Of the working satellites, how many radio/television/telephone channels do they account for? Please email full or partial answers to me. Thanks in advance!! John -- John A. Persoon (612) 481-3686 UUCP ihnp4!meccts!jap MECC Technical Services or jap@mecc.MN.ORG "Naturally, you didn't know I was wearing my special-super-thermal-d-long underwear!" -Adam West (Batman) ------------------------------ Date: 11 Jan 90 15:20:41 GMT From: att!drutx!druwa!rcb@ucbvax.Berkeley.EDU (BakerRC) Subject: Why did Solar Max fall but space junk stays up? I have a question about space junk. It has been said many times that the reason Solar Max (and presumably LDEF) fell to earth was because of the solar maximum swelling up the atmosphere causing more drag. Now I always thought that the bigger an object is the more likely it will be to stay in orbit, because (assuming constant density) the mass goes up as the cube of the diameter but the drag goes as the square. If these monster satellites can't stay up for even 1 solar cycle (and I believe they were fairly high) how the heck can all that tiny space junk stand a chance. It seems every 11 years it would get cleaned up. I'm obviously wrong, since space junk is a problem. So where am I wrong? ------------------------------ End of SPACE Digest V10 #417 *******************